Conclusive (?), a. [Cf. F. conclusif.] Belonging to a close or termination; decisive; convincing; putting an end to debate or question; leading to, or involving, a conclusion or decision.
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Secret reasons . . . equally conclusive for us as they were for them. Rogers.
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Conclusive evidence (Law), that of which, from its nature, the law allows no contradiction or explanation. -- Conclusive presumption (Law), an inference which the law makes so peremptorily that it will not allow it to be overthrown by any contrary proof, however strong.

Syn. -- Final; ultimate; unanswerable. See Final.
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